Association between LINC00657 and miR-106a serum expression levels and susceptibility to colorectal cancer, adenomatous polyposis, and ulcerative colitis in Egyptian population

The role of long non-coding RNA NORAD in digestive system tumors

In recent years, it has been discovered that the expression of long non-coding RNAs is highly deregulated in several types of cancer and contributes to its progression and development. Recently, it has been described that in tumors of the digestive system, such as colorectal cancer, pancreatic cancer, and gastric cancer, DNA damage-activated lncRNA (NORAD) was frequently up-regulated. The purpose of this review is to elucidate the functions of NORAD in tumors of the digestive system, emphasizing its involvement in important cellular processes such as invasion, metastasis, proliferation, and apoptosis. NORAD acts as a ceRNA (competitive endogenous RNA) that sponges microRNAs and regulates the expression of target genes involved in tumorigenesis. Thus, the mechanisms underlying the effects of NORAD are complex and involve multiple signaling pathways. This review consolidates current knowledge on the role of NORAD in digestive cancers and highlights the need for further research to explore its potential as a therapeutic target. Understanding the intricate functions of NORAD could elucidate the way for innovative approaches to cancer treatment.

Chronic Gastrointestinal Disorders and miRNA-Associated Disease: An Up-to-Date

Chronic gastrointestinal disorders such as inflammatory bowel diseases (IBDs) and irritable bowel syndrome (IBS) impose significant health burdens globally. IBDs, encompassing Crohn's disease and ulcerative colitis, are multifactorial disorders characterized by chronic inflammation of the gastrointestinal tract. On the other hand, IBS is one of the principal gastrointestinal tract functional disorders and is characterized by abdominal pain and altered bowel habits. Although the precise etiopathogenesis of these disorders remains unclear, mounting evidence suggests that non-coding RNA molecules play crucial roles in regulating gene expression associated with inflammation, apoptosis, oxidative stress, and tissue permeability, thus influencing disease progression. miRNAs have emerged as possible reliable biomarkers, as they can be analyzed in the biological fluids of patients at a low cost. This review explores the roles of miRNAs in IBDs and IBS, focusing on their involvement in the control of disease hallmarks. By an extensive literature review and employing bioinformatics tools, we identified the miRNAs frequently studied concerning these diseases. Ultimately, specific miRNAs could be proposed as diagnostic biomarkers for IBDs and IBS. Their ability to be secreted into biofluids makes them promising candidates for non-invasive diagnostic tools. Therefore, understanding molecular mechanisms through the ways in which they regulate gastrointestinal inflammation and immune responses could provide new insights into the pathogenesis of IBDs and IBS and open avenues for miRNA-based therapeutic interventions.

"Salivary LINC00657 and miRNA-106a as diagnostic biomarkers for oral squamous cell carcinoma, an observational diagnostic study"

BACKGROUND

Early detection and diagnosis of malignant tumors is critical for improving the survival rate and treatment outcomes of oral cancer. Thus, the current prospective investigation was designed to verify the role, sensitivity, and specificity of salivary LINC00657 and miRNA-106a as diagnostic markers in oral squamous cell carcinoma patients as compared to oral lichen planus (as an example of oral potentially malignant disorders) and normal individuals, and to show LINC00657 relation to miR-106a.

METHODS

A total of 36 participants were included, subdivided into 3 groups: Group I: 12 patients diagnosed with oral squamous cell carcinoma (OSCC). Group II: 12 patients diagnosed with oral lichen planus (OLP). Group III: 12 systemically free individuals with no oral mucosal lesions. Unstimulated salivary samples were collected from all participants to evaluate level of LINC00657 and miR-106a in different groups using quantitative real-time PCR.

RESULTS

OSCC showed the highest LINC00657 and lowest miR-106a fold change among included groups. Receiver Operating Characteristic (ROC) curve analysis of the two biomarkers for detecting OSCC revealed that LINC00657 had higher diagnostic accuracy (DA) (83.3%) compared to miR-106a (80.4%). As for detecting OLP, ROC analysis showed that miR-106a had higher (DA) (61%) compared to LINC00657 (52.5%). To discriminate OSCC from OLP, the diagnostic accuracy of both markers is the same (75%). Moreover, differentiating OSCC grades II and III, ROC analysis showed that miR-106a had lower (DA) (60%) compared to LINC00657 (DA) (83.3%).

CONCLUSIONS

Salivary LINC00657 and miR-106a could be promising diagnostic markers for oral squamous cell carcinoma. Salivary LINC00657 may differentiate oral squamous cell carcinoma from oral potentially malignant disorders with considerable diagnostic accuracy. Moreover, low levels of salivary miR-106a could have the potential to indicate malignancy.

TRIAL REGISTRATION

The study was retrospectively registered on clinicaltrial.gov with NCT05821179 (first trial registration in 26/3/2023), date of registration: 19/4/2023.

The significance of long non-coding RNAs in the pathogenesis, diagnosis and treatment of inflammatory bowel disease

Inflammatory bowel diseases (IBD) are a group of chronic relapsing gastrointestinal inflammatory diseases with significant global incidence. Although the pathomechanism of IBD has been extensively investigated, several aspects of its pathogenesis remain unclear. Long non-coding RNAs (lncRNAs) are transcripts with more than 200 nucleotides in length that have potential protein-coding functions. LncRNAs play important roles in biological processes such as epigenetic modification, transcriptional regulation and post-transcriptional regulation. In this review, we summarize recent advances in research on IBD-related lncRNAs from the perspective of the overall intestinal microenvironment, as well as their potential roles as immune regulators, diagnostic biomarkers and therapeutic targets or agents for IBD.

Long non-coding RNA signature in colorectal cancer: research progression and clinical application

Colorectal cancer is one of the top-ranked human malignancies. The development and progression of colorectal cancer are associated with aberrant expression of multiple coding and non-coding genes. Long non-coding RNAs (lncRNAs) have an important role in regulating gene stability as well as gene expression. Numerous current studies have shown that lncRNAs are promising biomarkers and therapeutic targets for colorectal cancer. In this review, we have searched the available literature to list lncRNAs involved in the pathogenesis and regulation of colorectal cancer. We focus on the role of lncRNAs in cancer promotion or suppression, their value in tumor diagnosis, and their role in treatment response and prognosis prediction. In addition, we will discuss the signaling pathways that these lncRNAs are mainly associated with in colorectal cancer. We also summarize the role of lncRNAs in colorectal precancerous lesions and colorectal cancer consensus molecular subgroups. We hope this review article will bring you the latest research progress and outlook on lncRNAs in colorectal cancer.

LINC00657 regulate colorectal carcinoma invasion and migration by enhancing heparanase expression through recruiting SMAD family member 2

Long noncoding RNAs are master regulators of several cancer phenotypes, such as cell growth, apoptosis, and motility. This study is designed to resolve the relevance of LINC00657 with tumor invasion and migration and its action mechanism in colorectal carcinoma (CRC). LINC00657 and HPSE levels were first examined in cancerous tissues from CRC patients and CRC cells. Then functional experiments were conducted to evaluate the abilities of HCT116 and SW620 cells to proliferate, migrate, and invade when LINC00657 or HPSE was knocked down, or LINC00657 knockdown and SMAD2 overexpression were simultaneously introduced. Snail and E-cadherin levels in the CRC cells were evaluated. Next, the binding between LINC00657 and SMAD2 or between SMAD2 and HPSE was determined. LINC00657-silencing HCT116 cells were inoculated into nude mice, and the tumorigenesis and the levels of Snail and E-cadherin were evaluated. LINC00657 and HPSE were increasingly expressed in CRC. Knockdown of LINC00657 or HPSE inhibited the malignant properties of CRC cells, decreased Snail expression, and strengthened E-cadherin level. LINC00657 and HPSE could both bind to SMAD2. SMAD2 overexpression counteracted the inhibiting effect of LINC00657 silencing on HPSE expression and the growth and invasion of CRC cells. In vivo experiments further verified the suppression of LINC00657 knockdown on tumor growth and metastasis. LINC00657 recruits SMAD2 to HPSE promoter region to elevate HPSE transcription, thus accelerating CRC invasion and migration.

Upregulated NORAD is implicated in apoptosis, inflammation, and oxidative stress in ulcerative colitis through the nuclear factor-κappaB signaling

BACKGROUND

Ulcerative colitis (UC) is a chronic inflammatory disease that affects the colon. It has been discovered that long non-coding RNA activated by DNA damage (NORAD) is upregulated in UC patient-derived serums, but its functional mechanism in UC has not been disclosed.

METHODS

Relative levels of NORAD in colonic mucosal tissues and TNF-α-stimulated human normal colonic mucosal cells (FHCs) were detected. Functional experiments were executed to evaluate the effects of NORAD silencing on TNF-α-induced FHC proliferation, apoptosis, inflammation, and oxidative stress. The molecular mechanism related to NORAD was predicted by starBase and confirmed by dual-luciferase reporter and RIP assays.

RESULTS

Our data exhibited higher levels of NORAD in UC patient-derived colonic mucosal tissues and TNF-α-stimulated FHCs. Functional experiments presented that NORAD inhibition impaired TNF-α-induced FHC apoptosis, inflammation, and oxidative stress. NORAD acted as a miR-552-3p sponge, and miR-552-3p silencing weakened NORAD inhibition-mediated effects on TNF-α-induced FHC apoptosis, inflammation, and oxidative stress. Myeloid differentiation primary response gene 88 (MYD88) was verified as a miR-552-3p target, and MYD88 overexpression whittled miR-552-3p mimic-mediated inhibition on TNF-α-induced FHC apoptosis, inflammation, and oxidative stress. Notably, TNF-α-induced NORAD regulated the nuclear factor-κappaB (NF-κB) signaling via the miR-552-3p/MYD88 axis.

CONCLUSION

NORAD participates in TNF-α-induced FHC apoptosis, inflammation, and oxidative stress via the NF-κB signaling via the miR-552-3p/MYD88 axis, offering new insights into the pathogenesis of UC.

MicroRNAs as potential biomarkers for the diagnosis of inflammatory bowel disease: a systematic review and meta-analysis

Objective

The clinical importance of aberrantly expressed microRNAs (miRNAs) in diagnosing inflammatory bowel disease (IBD) has not been well established, so was investigated in this systematic review and meta-analysis.

Methods

Articles in online databases from inception to March 17, 2021 were retrieved. Random effects meta-analysis was used to obtain sensitivity, specificity, positive (PLRs) and negative likelihood ratios (NLRs), diagnostic odds ratios (DORs), and areas under the curve (AUC) with 95% confidence intervals (CI) for IBD diagnosis.

Results

Of 117 studies reporting altered miRNA expression in IBD included in the systematic review, 15 involving 937 patients with IBD and 707 controls, 22 miRNAs, and two miRNA panels were eligible for meta-analysis. Pooled analyses showed a moderate diagnostic accuracy for miRNAs in the IBD diagnosis, with a sensitivity of 0.80 (95% CI: 0.79–0.82), specificity of 0.84 (95% CI: 0.82–0.86), DOR of 21.19 (95% CI: 13.90–32.31), and AUC of 0.89. Subgroup analyses revealed a better performance in patients with ulcerative colitis (AUC, 0.93) than Crohn’s disease (AUC, 0.84). Consistent upregulation of miR-21, miR-16, and miR-192 in blood with a high-moderate diagnostic accuracy was found in at least two studies.

Conclusions

These findings suggest miRNAs are credible diagnostic biomarkers in IBD.

Expression of lncRNAs NEAT1 and lnc-DC in Serum From Patients With Behçet’s Disease Can Be Used as Predictors of Disease

Background: Behçet’s disease (BD) is a chronic autoimmune disease. The early diagnosis of BD is very important to avoid serious and/or fatal complications such as eye damage, severe neurological involvement, and large vessel occlusion. New, sensitive biomarkers would aid in rapid diagnosis, the monitoring of disease activity, and the response to treatment.

Methods: This study’s aim is to identify two immune system-related BD biomarkers. We measured long non-coding RNAs (lncRNAs) NEAT1 (nuclear-enriched abundant transcript 1), and lnc-DC (lncRNA in dendritic cells) in serum by real-time polymerase chain reaction (RT-PCR) in 52 BD patients and 52 controls. We analyzed the association between NEAT1 and lnc-DC and the clinical parameters of BD. Receiver operating characteristic (ROC) curve analysis was performed to explore the diagnostic performance of the studied genes.

Results: Compared to controls, the significant upregulation of NEAT1 {median [interquartile range (IQR)] = 1.68 (0.38–7.7), p < 0.0001} and downregulation of lnc-DC [median (IQR) = 0.2 (0.12–1.39), p = 0.03] were detected in the sera collected from BD patients. Higher serum expression levels of NEAT1 and lnc-DC were significantly associated with the following clinical presentations: cutaneous lesions, vascular manifestations, articular manifestations, neurological manifestations, and higher disease activity score. Also, high NEAT1 levels were significantly associated with a negative pathergy test, while higher lnc-DC was significantly associated with a positive family history. ROC curves showed that NEAT1 and lnc-DC levels in serum could be used as predictors of BD with high specificity and fair sensitivity. NEAT1 had an area under the curve (AUC) of 0.692 (95% CI: 0.591–0.794, p = 0.001), and lnc-DC had an AUC of 0.615 (95% CI: 0.508–0.723, p = 0.043).

Conclusion: Serum lncRNAs NEAT1 and lnc-DC are biomarkers for BD.

Induction of lncRNA NORAD accounts for hypoxia-induced chemoresistance and vasculogenic mimicry in colorectal cancer by sponging the miR-495-3p/ hypoxia-inducible factor-1α (HIF-1α)

Hypoxic microenvironment represents the hallmark of solid tumors including colorectal cancer (CRC) and facilitates angiogenesis and chemoresistance, leading to poor prognosis. lncRNA NORAD acts as an oncogenic gene to orchestrate cancer progression by regulating cell proliferation and migration. Notably, an emerging study corroborates the elevation of NORAD during hypoxic conditions in pancreatic cancer. Nevertheless, its biological role in hypoxia-evoked CRC remains unclear. Herein, enhanced expression of NORAD and hypoxia-inducible factor-1α (HIF-1α) was validated in CRC tissues. Furthermore, there was a positive association between NORAD and HIF-1α in CRC tissues. CRC cells exposed to hypoxia exhibited a stronger ability to form vasculogenic mimicry (VM) and resistance to 5-fluorouracil (5-FU), concomitant with higher expression of NORAD. NORAD knockdown restrained hypoxia-induced VM formation and VM marker VE-cadherin expression. Moreover, knockdown of NORAD counteracted CRC cell resistance to 5-FU by decreasing cell viability and increasing cell apoptosis. Additionally, NORAD loss reduced hypoxia-induced HIF-1α expression and subsequent epithelial-mesenchymal transition (EMT) by increasing E-cadherin and inhibiting N-cadherin expression. Intriguingly, HIF-1α overexpression reversed NORAD downregulation-mediated inhibition of VM formation and 5-FU resistance. There was a low expression of miR-495-3p in CRC tissues. Furthermore, NORAD could act as a competitive endogenous RNA of miR-495-3p to regulate HIF-1α. Importantly, inhibition of miR-495-3p muted the efficacy of NORAD loss in hypoxia-induced EMT, VM, and chemoresistance. Thus, the current data highlight that NORAD knockdown may antagonize hypoxia-triggered CRC malignancy by suppressing VM formation and chemoresistance by sponging miR-495-3p/HIF-1α to regulate EMT, supporting a promising therapeutic target for refractory hypoxia in CRC.

New Circulating Circular RNAs with Diagnostic and Prognostic Potential in Advanced Colorectal Cancer

Circular RNAs (circRNAs) are a group of special endogenous long non-coding RNAs which are highly stable in the circulation, and, thus, more suitable as new biomarkers of colorectal cancer (CRC). The aim of our study was to explore the plasma expression levels of four circRNAs: has_circ_0001445, hsa_circ_0003028, hsa_circ_0007915 and hsa_circ_0008717 in patients with CRC and to evaluate their associations with clinicopathological characteristics and the clinical outcome of the patients. CircRNAs were extracted from patients’ plasma obtained prior to chemotherapy. Their expression levels were measured by qPCR and calculated applying the 2^−ΔΔCt method. The levels of all four circRNAs were significantly increased in the plasma of CRC patients. At the optimal cut-off values hsa_circ_0001445 and hsa_circ_0007915 in plasma could significantly distinguish between patients with or without metastatic CRC with 92.56% sensitivity and 42.86% specificity, and with 86.07% sensitivity and 57.14% specificity, respectively. The mean overall survival (OS) of patients with high/intermediate expression of hsa_circ_0001445 was 30 months, significantly higher in comparison with the mean OS of the patients with low expression—20 months (log-rank test, p = 0.034). In multivariate Cox regression analysis, the low levels of hsa_circ_0001445 were also associated with shorter survival (HR = 1.59, 95% CI: 1.02–2.47, p = 0.040). A prognostic significance of hsa_circ_0001445 for patients with metastatic CRC was established.

Long noncoding RNA KIF9-AS1 promotes cell apoptosis by targeting the microRNA-148a-3p/suppressor of cytokine signaling axis in inflammatory bowel disease

OBJECTIVE

Inflammatory bowel disease (IBD) is a chronic intestinal disease. This study was attempted to investigate the effects of long noncoding RNA KIF9-AS1 (KIF9-AS1) on the development of IBD and its underlying mechanism of action.

METHODS

Quantitative real time PCR (qRT-PCR) was implemented to examine the expression of KIF9-AS1 and microRNA-148a-3p (miR-148a-3p). The IBD mouse model was induced by dextran sulfate sodium (DSS). The body weight, disease activity index (DAI) score, colon length and histological injury were used to evaluate the colon injury. The levels of proinflammatory cytokines were measured by ELISA. In vitro, IBD was simulated by DSS treatment in colonic cells. Then the apoptosis of colonic cells was detected by flow cytometry assay. Furthermore, a dual-luciferase reporter assay was used to demonstrate the interactions among KIF9-AS1, miR-148a-3p and suppressor of cytokine signaling (SOCS3).

RESULTS

KIF9-AS1 expression was upregulated in IBD patients, DSS-induced IBD mice and DSS-induced colonic cells, whereas miR-148a-3p expression was downregulated. KIF9-AS1 silencing attenuated the apoptosis of DSS-induced colonic cells in vitro and alleviated colon injury and inflammation in DSS-induced IBD mice in vivo. Additionally, the mechanical experiment confirmed that KIF9-AS1 and SOCS3 were both targeted by miR-148a-3p with the complementary binding sites at 3'UTR. Moreover, miR-148a-3p inhibition or SOCS3 overexpression reversed the suppressive effect of KIF9-AS1 silencing on the apoptosis of DSS-induced colonic cells.

CONCLUSION

KIF9-AS1 silencing hampered the colon injury and inflammation in DSS-induced IBD mice in vivo, and restrained the apoptosis of DSS-induced colonic cells by regulating the miR-148a-3p/SOCS3 axis in vitro, providing a new therapeutic target for IBD.

Knockdown of LINC00657 inhibits the viability, migration and invasion of pancreatic cancer cells by regulating the miR-520h/CKS1B axis

Long non-coding RNA LINC00657 has a critical role in multiple cancers. The aim of the present study was to investigate the regulatory effect of LINC00657 in pancreatic cancer (PC) and reveal its molecular mechanism of function. The expression levels of LINC00657 and microRNA (miR)-520h were detected by reverse transcription-quantitative PCR in PC tissues and cell lines. MTT, wound healing and Transwell assays were used to detect cell viability, migration and invasion, respectively. Dual-luciferase reporter assay was utilized to examine the relationship between LINC00657 and miR-520h and that between miR-520h and cyclin-dependent kinases regulatory subunit 1 (CKS1B). Western blotting was performed to detect CKS1B expression. The expression levels of LINC00657 and CKS1B were enhanced and miR-520h expression level was reduced in PC tissues and cell lines compared with adjacent normal tissues or HPDE6 cells. LINC00657 knockdown decreased the viability, migration and invasion of PC cells. Additionally, LINC00657 targeted miR-520h and negatively modulated miR-520h expression. Furthermore, miR-520h overexpression inhibited the viability, migration and invasion of PC cells. In addition, miR-520h targeted CKS1B and reversely regulated CKS1B expression. miR-520h inhibition and CKS1B overexpression alleviated the inhibition effect of LINC00657 knockdown on the viability, migration and invasion of PACA-2 PC cells. In conclusion, the results of the present study demonstrated that LINC00657 knockdown repressed the viability, migration and invasion of PC cells via targeting the miR-520h/CKS1B axis, which may offer a future target for PC therapy.

Non-coding RNA Activated by DNA Damage: Review of Its Roles in the Carcinogenesis

Long intergenic non-coding RNA 00657 (LINC00657) or "non-coding RNA activated by DNA damage" (NORAD) is an extremely conserved and copious long non-coding RNA (lncRNA). This transcript has pivotal role in the preservation of genome integrity. Several researches have appraised the role of NORAD in the evolution of human cancers with most of them indicating an oncogenic role for this lncRNA. Several miRNAs such as miR-199a-3p, miR-608, miR-155-5p, miR-590-3p, miR-495-3p, miR-608, miR-202-5p, miR-125a-3p, miR-144-3p, miR-202-5p, and miR-30a-5p have been recognized as targets of NORAD in different cancer cell lines. In addition, NORAD has interactions with cancer-related pathways, particularly STAT, TGF-β, Akt/mTOR, and PI3K/AKT pathway. Over-expression of NORAD has been related with poor clinical outcome of patients with diverse types of neoplasms. Collectively, NORAD is a prospective marker and target for combating cancer.

Role of miRNA and lncRNAs in organ fibrosis and aging

Fibrosis is the endpoint of pathological remodeling. This process contributes to the pathogenesis of several chronic disorders and aging-associated organ damage. Different molecular cascades contribute to this process. TGF-β, WNT, and YAP/TAZ signaling pathways have prominent roles in this process. A number of long non-coding RNAs and microRNAs have been found to regulate organ fibrosis through modulation of the activity of related signaling pathways. miR-144-3p, miR-451, miR-200b, and miR-328 are among microRNAs that participate in the pathology of cardiac fibrosis. Meanwhile, miR-34a, miR-17-5p, miR-122, miR-146a, and miR-350 contribute to liver fibrosis in different situations. PVT1, MALAT1, GAS5, NRON, PFL, MIAT, HULC, ANRIL, and H19 are among long non-coding RNAs that participate in organ fibrosis. We review the impact of long non-coding RNAs and microRNAs in organ fibrosis and aging-related pathologies.

Association Between rs1859168/HOTTIP Expression Level and Colorectal Cancer and Adenomatous Polyposis Risk in Egyptians

LncRNA HOTTIP is a new lncRNA that is strictly linked to the susceptibility, growth, propagation, and prognosis of several human cancers together with colorectal cancer. lncRNA HOTTIP rs1859168 may confer colorectal cancer susceptibility through regulating its gene expression level. To elucidate its role in colorectal cancer risk, we genotyped rs1859168 A>C and measured serum HOTTIP expression level in colorectal cancer, adenomatous polyposis patients and controls by real-time polymerase chain reaction. The results displayed that rs1859168 A>C single-nucleotide polymorphism is a risk factor for colorectal cancer among adenomatous polyposis patients and controls, AC versus CC genotypes [adjusted odds ratio (OR) = 2.256, 95% confidence interval (CI) = 1.316-3.868, P = 0.003] when compared with controls and (adjusted OR = 9.521, 95% CI = 3.330-27.217, P < 0.0001) when compared with adenomatous polyposis. Serum HOTTIP was upregulated in the colorectal cancer group when compared with adenomatous polyposis or controls [median (interquartile range) = 3.64 (2.46-5.02) (P < 0.0001)]. A significant difference in serum HOTTIP was found to be associated with different rs1859168 genotypes. rs1859168 A>C and higher serum HOTTIP were significantly associated with distant metastasis, lymph nodes metastasis, and grade III of colorectal cancer. Both rs8159168 and high HOTTIP confer increased risk for colorectal cancer development. [Figure: see text].

HNRNPH1-stabilized LINC00662 promotes ovarian cancer progression by activating the GRP78/p38 pathway

Numerous studies suggest an important role for copy number alterations (CNAs) in cancer progression. However, CNAs of long intergenic noncoding RNAs (lincRNAs) in ovarian cancer (OC) and their potential functions have not been fully investigated. Here, based on analysis of The Cancer Genome Atlas (TCGA) database, we identified in this study an oncogenic lincRNA termed LINC00662 that exhibited a significant correlation between its CNA and its increased expression. LINC00662 overexpression is highly associated with malignant features in OC patients and is a prognostic indicator. LINC00662 significantly promotes OC cell proliferation and metastasis in vitro and in vivo. Mechanistically, LINC00662 is stabilized by heterogeneous nuclear ribonucleoprotein H1 (HNRNPH1). Moreover, LINC00662 exerts oncogenic effects by interacting with glucose-regulated protein 78 (GRP78) and preventing its ubiquitination in OC cells, leading to activation of the oncogenic p38 MAPK signaling pathway. Taken together, our results define an oncogenic role for LINC00662 in OC progression mediated via GRP78/p38 signaling, with potential implications regarding therapeutic targets for OC.

Long Non-coding RNA MEG3 Alleviated Ulcerative Colitis Through Upregulating miR-98-5p-Sponged IL-10

Ulcerative colitis (UC) is a refractory chronic colitis disease with the particularly complex cause. Recently, long noncoding RNAs (lncRNAs) have been reported to be related to the development of UC. LncRNA MEG3 has been proved to play an anti-inflammatory role in a variety of inflammatory diseases, which share similar pathogenesis with UC, indicating the potential involvement of lncRNA MEG3 in UC. This study aims to investigate the functional role and underlying mechanism of lncRNA MEG3 in UC. Gradient concentration of H2O2 (0, 20, 50, 100, and 200 μM) was used to induce Caco-2 damage models in vitro. Cell viability was detected by cell counting kit-8 (CCK-8) assay. LncRNA MEG3, miR-98-5p, and IL-10 levels in H2O2-treated Caco-2 cells were assessed by performing real-time quantitative polymerase chain reaction (RT-qPCR). Moreover, the binding relationship between lncRNA MEG3 and miR-98-5p, as well as the binding relationship between miR-98-5p and IL-10, was validated using dual-luciferase reporter assay. 2, 4, 6-Trinitrobenzenesulfonic acid solution (TNBS) was applied to induce ulcerative colitis in young rats. The body weight, disease activity index (DAI), length and weight of the colons, pathological scores of UC rats, reactive oxygen species (ROS), and inflammatory cytokines were determined to evaluate the effects of lncRNA MEG3 on the progression of UC. Besides, hematoxylin-eosin (HE) staining was exploited to observe histological changes of UC rat colons. In addition, western blotting analysis was also performed to evaluate the apoptosis and pyroptosis-related protein levels. Moreover, lncRNA MEG3, miR-98-5p, and IL-10 levels in UC rat colons were further assessed by RT-qPCR. Meanwhile, IL-10 expression was determined using immunohistochemistry. LncRNA MEG3 and IL-10 levels were distinctly decreased while miR-98-5p was increased in Caco-2 damage models and UC rats. Bioinformatics analysis predicted the binding sites of lncRNA MEG3 to miR-98-5p and miR-98-5p to IL-10. Besides, dual-luciferase reporter assay validated the negative correlation between lncRNA MEG3 and miR-98-5p, miR-98-5p, and IL-10. Overexpressed lncRNA MEG3 reduced. DAI scores and colon weight/length ratio improved UC ulceration. In addition, upregulation of lncRNA MEG3 relieved oxidative stress, inflammatory response, apoptosis, and pyroptosis of UC rat colons. LncRNA MEG3 overexpression alleviates the serve ulceration of UC rat colons by upregulating IL-10 expression via sponging miR-98-5p. To sum up, this study reveals the protective role of lncRNA MEG3 in the development of UC and may provide potential therapeutic targets for UC.

Novel Biomarkers in the Diagnosis of Benign and Malignant Gastrointestinal Diseases

BACKGROUND

Various noninvasive biomarkers have been used in the diagnosis, prognosis, and treatment of different gastrointestinal (GI) diseases for years. Novel technological developments and profound perception of molecular processes related to GI diseases over the last decade have allowed researchers to evaluate genetic, epigenetic, and many other potential molecular biomarkers in different diseases and clinical settings. Here, we present a review of recent and most relevant articles in order to summarize major findings on novel biomarkers in the diagnosis of benign and malignant GI diseases.

SUMMARY

Genetic variations, noncoding RNAs (ncRNAs), cell-free DNA (cfDNA), and microbiome-based biomarkers have been extensively analyzed as potential biomarkers in benign and malignant GI diseases. Multiple single-nucleotide polymorphisms have been linked with a number of GI diseases, and these observations are further being used to build up disease-specific genetic risk scores. Micro-RNAs and long ncRNAs have a large potential as noninvasive biomarkers in the management of inflammatory bowel diseases and GI tumors. Altered microbiome profiles were observed in multiple GI diseases, but most of the findings still lack translational clinical application. As of today, cfDNA appears to be the most potent biomarker for early detection and screening of GI cancers. Key Messages: Novel noninvasive molecular biomarkers show huge potential as useful tools in the diagnostics and management of different GI diseases. However, the use of these biomarkers in real-life clinical practice still remains limited, and further large studies are needed to elucidate the ultimate role of these potential noninvasive clinical tools.

NORAD, a critical long non-coding RNA in human cancers

The ^incidence of cancer is growing worldwide, and it is becoming the most common cause of death. Long non-coding RNAs (lncRNAs) are a group of RNA transcripts with a length larger than 200 nucleotides that cannot encode proteins or peptides. LncRNAs regulate different biological functions by controlling gene expressions at transcriptional, translational, and post-translational levels. Non-coding RNA activated by DNA damage (NORAD) is a highly conserved lncRNA necessary for genome stability. LncRNA NORAD is dysregulated in various types of cancers. This biomarker has been involved in numerous processes associated with carcinogeneses, such as cell proliferation, apoptosis, invasion, and metastasis. In this paper, we reviewed the role of lncRNA NORAD and its biological functions in various human cancers to provide future research insights.

MicroRNAs for Diagnosis and Treatment of Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer worldwide, with high morbidity and mortality rates. The diagnosis and treatment of CRC have the most significant value for disease- free survival. Early diagnosis and early surgical resection are generally considered to be the most effective ways to reduce CRC mortality. In the past few years, many researchers have focused on the role of microRNAs in different tumors, making the functions of microRNAs gradually clear. The present study reviews the role of microRNAs in the diagnosis and treatment of colorectal cancer. Compared with the usual diagnosis methods and biomarker, circulating microRNAs can be promising new effective biomarkers for CRC diagnosis and treatment.

Serum long noncoding RNAs FAS-AS1 & PVT1 are novel biomarkers for systemic lupus erythematous

Background: Systemic Lupus Erythematous (SLE) is a chronic systemic autoimmune disorder whose diagnosis depends on combination of multiple factors. Circulating lncRNAs could serve as diagnostic non-invasive biomarkers for SLE. We hypothesised that serum FAS-AS1 and PVT1 are new biomarkers for SLE that relate to clinical features and laboratory markers. Materials and Method: Measurement of serum FAS-AS1 & PVT1 by qRT-PCR, analysis of the association between two RNAs and the clinical data, activity index and laboratory markers by standard routine methods. Results: There was a significant relative increased serum FAS-AS1 (median (IQR) 2.19 (0.13-8.62) and a significant reduced PVT1 (median (IQR) 0.52 (0.01-7.55) in SLE patients compared to controls (P < 0.0001 for FAS-AS1 and = 0.007 for PVT1). Serum FAS-AS1 and PVT1 were positively correlated (r= 0.37, P = 0.001). Higher FAS-AS1 was significantly linked with nephritis (P = 0.011), positive anti-dsDNA (P= 0.01) and lower serum PVT1 was significantly associated with oral ulcers (P= 0.023), photosensitivity (P= 0.017), and neurological manifestations (P= 0.041). Serum PVT1 negatively correlated with age (r= -0.52, P< 0.0001) and ESR level (r= -0.29, P= 0.011) in SLE patients. No correlation between disease activity and serum FAS-AS1 or PVT1 was detected. Conclusions: Our study provides evidence that serum FAS-AS1 and PVT1 are new biomarkers for SLE.

Analysis of the expression profile of long non-coding RNAs MALAT1 and THRIL in children with immune thrombocytopenia

BACKGROUND/AIMS

Pediatric immune thrombocytopenia (ITP) is an autoimmune disease; whose etiology is not exactly understood and seems to be highly multifactorial. Long non-coding RNAs (lncRNAs) are key regulators of different actions, which contribute to the development of many autoimmune diseases. To gain a further understanding, we estimated the relative expression of lncRNAs Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and tumor necrosis factor-α (TNF-α) and heterogeneous nuclear ribonucleoprotein L (hnRNPL) immune-regulatory lncRNA (THRIL) in pediatric ITP.

METHODS

In this case-control study, analysis of the expression profiles of these lncRNAs in blood samples from children with ITP and healthy controls (HCs) using quantitative real-time PCR was done. The association of MALAT1 and THRIL with ITP clinical features and their potential usage as non-invasive circulating biomarkers for ITP diagnosis was also evaluated. The receiver operating characteristic curve was constructed, and an area under the curve was analyzed.

RESULTS

Both lncRNAs MALAT1 and THRIL were significantly upregulated in ITP patients in comparison to HCs ( p < .0001 and = .001 respectively). In addition, there was a positive significant correlation between the expression level of both biomarkers among patients (r = 0.745, p < .0001). At cutoff points of 1.17 and 1.27 for lncRNAs MALAT1and THRIL, respectively, both biomarkers had an excellent specificity (100% for both) and fair sensitivity (63.6 and 73.3% for lncRNAs MALAT1and THRIL, respectively). Improvement of biomarkers specificity was obtained by evaluation of the combined expression of both biomarkers. Serum lncRNAs MALAT1 and THRIL could be used as potential biomarkers in differentiating childhood ITP patients and HCs.

Effect of LINC00657 on Apoptosis of Breast Cancer Cells by Regulating miR-590-3p

Objective

To investigate the effect of LINC00657 on breast carcinoma by regulating miR-590-3p.

Methods

Ninety-seven cases with breast carcinoma who were admitted to Qingdao Chengyang People’s Hospital were collected. The breast carcinoma (n=97) and tumor-adjacent tissues (n=97) of patients were collected during the operation with the permission of the patients. The expressions of LINC00657 and miR-590-3p were detected in breast carcinoma cells and tissues. The breast carcinoma cells were transfected and their proliferation, migration, invasion and apoptosis were detected.

Results

LINC00657 was highly expressed in breast carcinoma tissues, while miR-590-3p was reduced (P<0.05). The proliferation, invasion and migration of cells transfected with si-LINC00657 or miR-590-3p-mimics were significantly inhibited, and the apoptosis rate increased, resulting in the up-regulation of the expressions of apoptosis-related proteins Bax and Caspase-3 and the reduction of Bcl-2 (P<0.05). After si-LINC00657 or miR-590-3p-mimics, the level of GOLPH3 decreased. Through double luciferase report and RIP experiment, it was confirmed that LINC00657 could act as a sponge of miR-590-3p to negatively regulate its expression. After correlation analysis, it was concluded that there was a negative correlation between LINC00657 and miR-590-3p. Rescue experiments concluded that co-transfection of si-LINC00657+miR-590-3P-inhibitor could reverse the inhibitory action of si-LINC00657 on breast carcinoma cells.

Conclusion

LINC00657 can participate in the biological behavior process of breast carcinoma by regulating miR-590-3p/GOLPH3 signal.

Long noncoding RNA LINC00657 induced by SP1 contributes to the non-small cell lung cancer progression through targeting miR-26b-5p/COMMD8 axis

Non-small-cell lung cancer (NSCLC) is a kind of lung cancer with high incidence and poor outcomes all over the world. Studies have validated that the upregulation of long noncoding RNA LINC00657 is related to several cancers. Nevertheless, the underlying regulatory mechanism of LINC00657 in NSCLC has not been well elucidated. In the present study, quantitative reverse-transcription polymerase chain reaction (RT-qPCR) revealed that LINC00657 level was apparently elevated in NSCLC cells. Loss-of function assays demonstrated that LINC00657 silence retarded cell proliferation and migration in NSCLC cells. Moreover, the chromatin immunoprecipitation result identified the transcription factor SP1 could bind with LINC00657 promoter, and RT-qPCR proved SP1 positively regulated LINC00657 expression in NSCLC cells. In addition, the mechanistic investigations unveiled that LINC00657 was an endogenous sponge of miR-26b-5p and therefore boosted the expression of copper metabolism MURR1 domain-containing 8 (COMMD8), one of the targets of miR-26b-5p. Besides, miR-26b-5p could negatively regulate LINC00657 or COMMD8 in NSCLC cells. With the application of rescue assays, we uncovered that overexpression of COMMD8 partly mitigated the impairment of LINC00657 repression on NSCLC cell proliferation and migration. Together, our study illustrated that SP1-stimulated LINC00657 promoted NSCLC progression through targeting miR-26b-5p/COMMD8 axis, offering a novel potential therapeutic target for NSCLC.

Association analyses of a genetic variant in long non-coding RNA MEG3 with breast cancer susceptibility and serum MEG3 expression level in the Egyptian population

BACKGROUND

LncRNA MEG3 rs7158663 has been shown to confer cancer susceptibility, maybe through altering its gene expression level.

OBJECTIVE

We aimed to weigh the effect of rs7158663 on MEG3 serum level and breast cancer susceptibility.

METHODS

We genotyped rs7158663 G > A and measured serum MEG3 in 150 breast cancer, 95 fibroadenoma , and 154 controls by the TaqMan method.

RESULTS

The presence of rs7158663 G > A is a risk factor for breast cancer among fibroadenoma patients and controls, AA vs. GG genotypes (OR = 6.320, 95% CI = 2.587-15.439, P< 0.0001 when compared to controls and OR = 10.825, 95% CI = 1.929-60.742, P= 0.007 when compared to fibroadenoma). Decreased serum MEG3 was observed in breast cancer group when compared with fibroadenoma and/or controls [median (IQR) = 0.43 (0.27-0.55)] (P< 0.0001). However, increased serum MEG3 was noted in fibroadenoma group when compared with controls (P< 0.0001). A significance decreased serum MEG3 was found to be associated with mutant A allele than with wild G allele (P< 0.0001). The results showed that rs7158663 and lower MEG3 were significantly associated with patients with higher TNM staging and larger tumor size > 5 cm.

CONCLUSION

The presence of both rs7158663 and low MEG3 are diagnostic and unfavorable prognostic factors for BC patients.

Increased expression of long noncoding RNA GAS6-AS2 promotes proliferation and inhibits apoptosis of melanoma cells via upregulating GAS6 expression

Long noncoding RNAs (lncRNAs) are frequently aberrantly expressed and involved in many cancers, including melanoma. GAS6-AS2 was a recently identified cancer-related lncRNA. However, the expression, roles, and functional mechanisms of GAS6-AS2 in melanoma remain unknown. In this study, we found that lncRNA GAS6-AS2 is significantly elevated in melanoma tissues and cells. Elevated expression of GAS6-AS2 is positively correlated with advanced stages and poor prognosis in melanoma. Functional assays demonstrated that ectopic expression of GAS6-AS2 promotes proliferation and inhibits apoptosis of melanoma cells. In contrast, knockdown of GAS6-AS2 inhibits proliferation and promotes apoptosis of melanoma cells. Furthermore, in vivo functional assays showed that GAS6-AS2 promotes melanoma xenograft growth. Mechanistically, we found that GAS6-AS2 upregulates GAS6 expression, promotes GAS6 secretion, and activates AXL/AKT/ERK signals. The expression of GAS6 was positively correlated with that of GAS6-AS2 in melanoma tissues. In addition, deficiency of GAS6 reverses the biological roles of GAS6-AS2 overexpression in melanoma cell proliferation and apoptosis. Collectively, our data identified GAS6-AS2 as an oncogenic lncRNA in melanoma via activation of GAS6/AXL/AKT/ERK signals. Our data suggested that GAS6-AS2 may be a novel potential prognostic biomarker and therapeutic target for melanoma.